Old Advisory Events
The information herein is NOT intended for use as a weather forecast. The Air District DOES NOT forecast but solely compiles information from both the Phoenix and San Diego National Weather Offices to relay information concerning potential changes in ambient air concentrations that may impact the public.
|September 26 2016|
|High wind levels have the potential to suspend particulate matter into the air. High levels of PM10 may pose an impact to public health. It is recommended that active children and adults, and people with respiratory disease, such as asthma, limit their outdoor activities.
Potential increases in PM10 concentrations may increase to moderate or unhealthy level.
|Imperial County Weather Synopsis|
|SYNOPSIS FROM THE SAN DIEGO OFFICE
High pressure over the interior west will be weakening through Wednesday, which will allow easterly winds to decrease. At the same time, a low pressure area will be drifting north over Southern California bringing more clouds, higher humidity, cooling, and a chance for scattered showers and isolated thunderstorms, especially over the mountains. Cooler for the latter half of the week as onshore flow and the marine layer slowly return.
Mountain wave clouds developed this morning and increased into the early afternoon, creating a nearly solid cloud deck over much of central San Diego County and portions of Riverside County. More clouds covered southern AZ and should spread westward tonight into Tuesday. Despite the clouds, subsidence driven heating has been maximized along the coastal areas today where early afternoon temperatures were running 95 to 105 degrees. It was a bit cooler inland across the valleys to the foothills but still quite warm. Despite the withering heat, previous heat waves this time of year make it difficult to break records, so expect few. a Heat Advisory remains in effect through 8 PM PDT.
It has been breezy, even along and off the coast due to the east winds, and yet, they have not been quite as strong as expected, so the Wind Advisory has been cancelled. Surface pressure gradients were running around 10 MBS offshore from NV to KSAN but still about flat to the lower deserts.
SYNOPSIS FROM THE PHOENIX OFFICE
A developing low pressure system over northwest Mexico and the Baja Peninsula will slowly move north toward southwest Arizona by late today. Easterly to southeasterly flow ahead of this system will bring increasing amounts of cloudiness and moisture, and cooler temperatures to the region, along with a slight chance for showers and thunderstorms from late this afternoon onward into Thursday. Clear skies and normal temperatures will return from Friday into next weekend, as much drier westerly flow aloft becomes established over the Desert Southwest.
|Weather Story Phoenix Station||Weather Story San Diego Station|